1. Field
The present invention relates to a liquefied natural gas (LNG) storage tank, and more particularly, an LNG storage tank having an improved insulation structure.
2. Discussion of the Related Technology
In general, liquefied natural gas (LNG) is obtained by causing natural gas, one of fossil fuels, to be liquefied. An LNG storage tank is classified into a ground storage tank, which is installed on the ground or buried in the ground according to installation positions, and a mobile storage tank, which is mounted on transportation means such as vehicles and ships. The aforementioned LNG is stored in a cryogenic state and is explosive when it is exposed to shock. Thus, the LNG storage tank should be constructed such that shock resistance and liquid-tight characteristics thereof can be firmly maintained.
Japanese Patent Laid-Open Publication No. 2002-181288 discloses a liquefied natural gas storage tank including an outer tank made of concrete, insulation covering an inner surface of the outer tank, and two membranes.
This section is to provide a general background information, and does not constitute an admission of prior art.